Vacuum and compression pump



Jan. 16, 1934-. MCCARTHY 1,943,767

VACUUM AND COMPRESSION PUMP I Original Filed May 9, 1931 Patented Jan. 16, 1934 UNETEE stares PATENT GFFlCE Edward F. Mcilarthy, Chicago, 111., assignor of one-half to Charles H. McCarty, Chicago, 111.

Application May 9, 1931, Serial No. 536,191 Renewed December 8, 1933 6 Claims. (Cl. 230---108) This invention relates to improvements in Vacuum and compression pumps and more particularly a pump for creating vacuum or producing pressure and commonly known, as a vacuum pump.

One object of the invention is to provide a pump of the character indicated which is efficient in operation, simple and inexpensive in construction, and having minimum number of wearing parts.

More specifically, an object of the invention is to provide a centrifugal pump of the type indicated for handling fluids wherein the rotor or impeller operates in a closed liquid circuit, the rotor being so designed that the frictional resistance to the fluids passing therethrough is reduced to a minimum.

Still another object of the invention is to provide a vacuum pump of the type indicated wherein the rotor has the passage or passages therein for the fiuid being. handled, always in communication with the admission passage or port for the iiuid to the rotor.

Other objects of the invention will more clearly appear from the description and claims hereinafter following.

In the drawing forming a part of this specification, Figure l is a vertical sectional view of a pump having the improvements incorporated therein, the section corresponding substantially to the line 1-1 of Figure 2. Figure 2 is a vertical sectional view at right angles to the sectional view of Figure 1 and corresponding substantially to the line 22 of Figure 1. And Figure 3 is a vertical sectional View corresponding to the line 3-3 of Figure 1.

Inv said drawing, the housing or casing of the pump is indicated generally by the reference character A; the rotor by the reference character 1 and the shaft therefor by the reference character 3.

The casing A is of generally rectangular form, comprised of preferably two sections with a vertical parting line connected together as by bolts 20-20, said casing having vertical front and rear walls 2l-21 and vertical end walls 22-22. 011 its interior, the casing is provided with a vertically extending partition 5, dividing the casing into two chambers or compartments in communication with each other at the top of the casing above the partition 5, as clearly shown in Figure 1. In axial alinement with the rotor and shaft, said partition is provided with a circular opening 23 for the purpose hereinafter described.

referably formed integrally with the rear wall 21 is a web section 24 providing an admission passage 11 for the fluid to be handled by the rotor. At the lower end, the section 24 terminates in an annular sleeve 25 in which is rotatably mounted the hollow sleeve or journal 26 of the rotor, said hollow sleeve being obviously in communication with the inlet passage 11. The casing is adapted to be drained when necessary by means of the removable threaded plug 9 and the air or other fluid which arises from the liquid is within the casing is adapted to pass out through outlet 12.

The shaft 3, to which the rotor is preferably keyed, as indicated at 27, is journalecl at its outer end in an outboard bearing 6, the shaft 3 carrying a coupling l adapted to be connected with any suitable driving mechanism for effecting rotation of the shaft and rotor. Where the shaft passes into the casing A, packing '7 is employed with which is associated an adjustable gland 8, as indicated.

integrally formed with the partition 5 and concentric with the axis of the rotor shaft, are one or more arcuate flanges or stationary valves 2, the same being extended inwardly of that chamber in which the rotor is mounted. In the drawing, two of such flanges or valves 2 are shown, the same being diametrically disposed and each extending through an arc of approximately 90, thus leaving two intervening openings or ports 28 also diametrically disposed and alternating with the valves.

The rotor 1, in addition to the sleeve 26, is formed with a central hub 29 keyed to the shaft as hereinbefore described; a web section 30; another web section 31 inwardly spaced from the web section 30 and an outer web section 32, the lat er running in proximity to the partition 5, as best shown in Figure 1.

Between the web sections 30 and 31 is formed a radially extending chamber 33 which is in communication with the axial opening 34 within the sleeve 26 and hence in communication with the intake passage 11 for the fluid to be handled. Also formed integrally with the rotor and disposed between the two web sections 30 and 32 is a plurality of impeller vanes 14-44, each of which extends substantially spirally outwardly or in the form of an involute curve from its advance edge 35 to the periphery of the rotor, as indicated at 36. Four of such vanes are shown, the same being uniformly spaced. The advance edges of the vanes are so located that they just clear the valves 2, as best indicated in Figure 3 and it will also be noted that the outer terminal edges 36 of the vanes do not overlap, circumferentially, the forward or advance edges of the next succeeding vanes. With this construction, it is evident that no closed channels are formed, either by or between any of the sets of vanes, this being done in order to minimize to the greatest possible extent, the frictional resistance to the movement of the liquid and fluids relative to the rotor, as the latter is rotated. On the inner side of each vane 14 and preferably immediately adjacent the forward edge thereof, the web section 30 of the rotor is provided with openings 15 to provide communication with the chamber 33, as obvious.

The operation of the pump is as follows, assuming liquid in the casing A, as indicated, and the pump connected up to any source of fluid to be handled, such as a vacuum heating system wherein the air and any entrapped moisture is admitted through the passage 11. As the rotor or impeller 1 is rotated rapidly in a clockwise direction, as viewed in Figure 3, the liquid enters the rotor behind the vanes through the openings or ports 28 and, as the rotor continues its rotation, slugs of the liquid are successively caught on the outer sides of the vanes 14 and thrown off centrifugally. As the forward edges of the vanes successively pass over the stationary arcuate flanges or valves 2, further admission of the liquid to the insides of the vanes is thereby cut oif while the vanes are passing over said valves 2, thus setting up or creating a isplacement area or area of reduced pressure. As said area of displacement or reduced pressure is formed in the passage of the vanes sue cessively over the valves 2, the fluid to be handled is drawn in through the passages and chambers 11, 34 and 33, finally through the openings 15 and then, as the vanes of the rotor pass off of the valves 2, the fluid so drawn in is mingled with the liquid and rises through the body of liquid 10 to the top thereof, where it is allowed to pass off through the outlet 12.

With the construction as shown and described, it is evident that the fluid ports 15 are always in communication with the intake passage 11; and there is a minimum frictional resistance offered to all movements of the fluid and liquid relative to the rotor parts.

As will be obvious to those skilled in the art, various changes and modifications may be made as, for instance, in the number of vanes and stationary valves, without departing from the spirit of the invention. All changes and modifications coming within the scope of the claims appended hereto are contemplated.

What is claimed is:

1. In a pump or the character described, the combination with a casing vertically partitioned to provide two compartments for a circulating liquid; of a rotor mounted in one compartment and adapted to operate immersed in the liquid, said rotor having an impeller vane and a fluid passage adjacent thereto, said passage having a delivery port on the radially underside of the vane and a laterally opening admission port arranged for communication with a fixed passage for conducting the fluid to the rotor; and means for alternately opening to and shutting off communication from the liquid from the other compartment to the rotor, whereby a reduced pressure area is developed in the rotor fluid passage as the rotor is alternately shut off from communication with said second named compartment.

2. In a pump of the character described, the c mbination with a casing for a circulating 2 uid; of a rotor mounted therein to rotate about a horizontal axis and adapted to operate immersed in the liquid; a stationary valve having an admission port to the rotor for the cir culating liquid, said rotor having an impeller vane which rotates past said stationary valve and its admission port; means providing an admission chamber for the fluid to be handled by the rotor, the rotor having a passage for the fluid to pass therethrough; and means providin constant communication between said passage and the fluid chamber, the fluid and liquid being admitted to the rotor from axially opposite directions.

3. In a pump of the character described, the combination with a casing for a circulating liquid; of a valve disposed in said casing having a plurality of fixed sections with circumferentially alternated liquid ports; a rotor having a piurality of vanes, each extending substantially spirally outward from an intermediate point on the rotor and outwardly of the valve to the periphery of the rotor, the vanes being so circumicrentially spaced that circumferential overlapping of the vanes is avoided; means for eifecting reduced pressure areas on the radially under sides of the vanes as the same pass successively over said flxed valve sections; and means providing communication for the fluid to be handled with said reduced pressure areas.

l. In a pump of the character described, the combination with a casing for a circulating liquid and having a partition dividing the same into two chambers; of a rotor mounted entirely in one of said chambers, the rotor having an axial admission port for the fluid to be'handled thereby, said rotor being provided with impeller vanes and openings adjacent thereto for delivering the fluid and which openings are in communication with said admission port, said partition having an opening therethrough foradmitting the liquid to the rotor; and fixed valves for successively and intermittently shutting ofi communication between said partition opening and said rotor openings as the rotor is rotated.

5. In a pump of the character described, the combination with a casing for a circulating liquid; of a vertical partition within said casing dividing the latter into two chambers communicating at the top of the casing, said partition having an opening therein and equally distantly circumierentially spaced arcuate flanges projecting horizontally into one of the chambers; a rotor mounted in said last mentioned chamber to rotate about an axis concentric with said flanges, said rotor having a hub, spaced, radially disposed web sections forming a chamber, and a plurality of uniformly circumferentially spaced vanes, each vane extending from the periphery of the rotor spirally inwardly to a point intermediate the periphery and axis of the rotor, said vanes being so disposed as to surround said flanges and rotate therearound, said rotor being provided with openings correspending in number to the vanes and which communicate with said rotor chamber for admitting the fluid to be handled; and means providing a communicating passage to said rotor chamber for admission of the fluid thereto.

6. In a pump of the characterdescribed, the

combination with a casing for a circulating liquid; of a vertical partition within said casing dividing the latter into two chambers communicating at the top of the casing, said partition having an opening therein and equally distantly circumferentially spaced arcuate flanges projecting horizontally into one of the chambers; a rotor mounted in said last mentioned chamber to rotate about an axis concentric with said flanges, said rotor having a hub, spaced, radially disposed web sections forming a chamber, and a plurality of uniformly circumferentially spaced vanes, each vane extending from the periphery of the rotor spirally inwardly to a point intermediate the periphery and axis of the rotor,

said vanes being so disposed as to surround said flanges and rotate therearound, said rotor being provided with openings corresponding in number to the vanes and which communicate with said rotor chamber for admitting the fluid to be handled; and means providing a communicating passage to said rotor chamber for admission of the fluid thereto, said openings in the rotor being disposed on the radially under sides of the vanes adjacent the forward edges thereof and the outer peripheral edge of each vane being terminated so as to avoid circumferentially overlying the forward edge of the next succeeding vane.

EDWARD F. MCCARTHY. 

